Based on the life cycle assessment (LCA) method, the production processes of PBAT packaging bag and PBAT/starch (75%PBAT+25% starch) packaging bag were compared by using eFootprint software, and the environmental impact of PBAT based packaging bag was quantitatively analyzed. The results showed that the potential of PBAT/ starch packaging bag in CO2 emission and primary energy consumption (PED) was significant, and the contribution of PBAT/ starch packaging bag could be reduced by 14.53% and 6.44%, respectively. The impacts of PBAT packaging bagon PED, CO2 emission andindustrial water use (IWU) were obvious. The index values of PBAT packaging bag were 9.47E+4 MJ, 4.18E+3 kg, 4.52E+3 kg for 1 t production, while the index values of PBAT/starch package bag were 8.86E+4 MJ, 3.81E+3 kg and 5.04E+3 kg respectively. The ECER-135 comprehensive index value of PBAT packaging bag and PBAT/starch packaging bag were 1.36E-8 and 1.25E-8 respectively, indicating the environmental load of PBAT based packaging bag was reduced by 8.1% after the modification with starch. The environmental load of PBAT based packaging bags was mainly from PBAT based particles production stage, and among the contributors in the PBAT and PBAT/starch projects, the contributors of SO2 was the largest, followed by PED. Therefore, SO2, PED, NOx and COD indicators rankingabove CO2 should be taken into consideration to avoid the environmental problem-shifting.